Image forming apparatus with a guide assembly

ABSTRACT

An image forming apparatus includes a transport path and a guide assembly. The transport path is configured to convey a recording medium. The guide assembly is configured to guide the recording medium in the transport path. Further, the guide assembly includes a surface member and a base member. The surface member has first and second surfaces of a similar shape on opposite sides thereof. The base member is configured to support the surface member. The surface member and the base member are removably connected in one of first and second assembled forms. The first surface serves to receive the recording medium and the second surface faces the base member in the first assembled form. The second surface serves to receive the recording medium and the first surface faces the base member in the second assembled form.

PRIORITY STATEMENT

The present patent application claims priority under 35 U.S.C. §119 upon Japanese patent application, No. JP2006-309123 filed on Nov. 15, 2006 in the Japanese Patent Office, the entire contents of which are hereby incorporated herein by reference in their entirety.

BACKGROUND

1. Field

Example embodiments generally relate to an image forming apparatus with a guide assembly; for example to an image forming apparatus provided with a guide assembly for a transport path, which may be readily maintained.

2. Discussion of the Background

An image forming apparatus, such as a copier, printer, facsimile, or multifunction peripheral with multiple imaging functions has a transport path for conveying recording media such as paper sheets. A transport path in a conventional image forming apparatus generally has guide members, such as belts or plates, that facilitate movement of recording media along the transport path. These guide members require regular maintenance as they become covered with paper dust and other contaminants built up through use, which may lead to smears on conveyed recording media and/or obstacles in the transport path.

To provide effective maintenance for such guide members, various methods have been designed. For example, one conventional image forming apparatus includes a cleaning member to remove dust and grime from a guide member surface when maintenance is needed. Another conventional image forming apparatus includes a belt cleaner to remove ink smears from a conveyor belt. Further, another conventional image forming apparatus uses a sheet-shaped cleaning member that cleans a conveyor belt surface while traveling along a transport path.

Although effective in removing accumulated paper dust and non-adhering particles, these methods are insufficient to remove sticky deposits of adhesives and glue adhering to the guide member surface. The adhering deposits are derived from self-adhesive products using adhesives and glue, such as labels or stickers, onto which printing is applied. When a self-adhesive product is conveyed along a transport path, adhesives may leak out or rub off from edges and adhere to the transport path surface to build up sticky deposits.

Typically, a transport path inside an image forming apparatus includes a curved portion provided with a guide plate, allowing a conveyed recording medium to turn to change transport direction. The guide plate serves to receive and guide the recording medium therealong, and is therefore prone to collect adhesive contaminants derived from recording media, which may lead to malfunctions such as paper creases and jams during media transport.

As conventional cleaning methods have been ineffective in removing adhesive deposits, maintaining an image forming apparatus required replacement of contaminated guide members. This makes maintenance burdensome and costly, putting a heavy load on users of image forming apparatuses.

SUMMARY

This patent specification describes, in at least one example embodiment, an image forming apparatus with a guide assembly for a transport path, which may be readily maintained.

In at least one example embodiment, an image forming apparatus includes a transport path and a guide assembly. The transport path is configured to convey a recording medium. The guide assembly is configured to guide the recording medium in the transport path. Further, the guide assembly includes a surface member and a base member. The surface member has first and second surfaces of a similar shape on opposite sides thereof. The base member is configured to support the surface member. The surface member and the base member are removably connected in one of first and second assembled forms. The first surface serves to receive the recording medium and the second surface faces the base member in the first assembled form. The second surface serves to receive the recording medium and the first surface faces the base member in the second assembled form.

This patent specification further describes, in at least one example embodiment, an image forming apparatus with a guide assembly for a transport path, which may be readily maintained.

In at least one example embodiment, an image forming apparatus includes a transport path and a guide assembly. The transport path is configured to convey a recording medium. The guide assembly is configured to guide the recording medium in the transport path. Further, the guide assembly includes a surface member and a base member. The surface member has a plurality of layers superimposed and removably bonded together, and is configured to receive the recording medium at an outermost layer of the plurality of layers. The base member is configured to support the surface member.

This patent specification further describes, in at least one example embodiment, an image forming apparatus with a guide assembly for a transport path, which may be readily maintained.

In at least one example embodiment, an image forming apparatus includes a transport path and a guide assembly. The transport path is configured to convey a recording medium. The guide assembly is configured to guide the recording medium in the transport path. Further, the guide assembly includes a surface member and a base member. The surface member is transparent, and is configured to receive the recording medium at a guide surface thereof. The base member has a sight hole, and is configured to support the surface member so that condition of the guide surface is observable through the sight hole.

BRIEF DESCRIPTION OF THE DRAWINGS

A more complete appreciation of the disclosure and many of the attendant advantages thereof will be readily obtained as the same becomes better understood by reference to the following detailed description when considered in connection with the accompanying drawings, wherein:

FIG. 1 is a cross-sectional diagram illustrating an image forming apparatus according to at least one example embodiment;

FIG. 2A is an enlarged, partial cross-sectional view illustrating the image forming apparatus of FIG. 1;

FIG. 2B is an enlarged, partial cross-sectional view illustrating the image forming apparatus of FIG. 1;

FIG. 3 is an example schematic illustration of a guide assembly for use in the image forming apparatus of FIG. 1;

FIG. 4 is an example schematic illustration of another guide assembly for use in the image forming apparatus of FIG. 1;

FIGS. 5A and 5B are example schematic illustrations of another guide assembly for use in the image forming apparatus of FIG. 1; and

FIG. 6 is an example schematic illustration of another guide assembly for use in the image forming apparatus of FIG.

DETAILED DESCRIPTION OF EXAMPLE EMBODIMENTS

It will be understood that if an element or layer is referred to as being “on”, “against”, “connected to” or “coupled to” another element or layer, then it may be directly on, against, connected or coupled to the other element or layer, or intervening elements or layers may be present. In contrast, if an element is referred to as being “directly on”, “directly connected to” or “directly coupled to” another element or layer, then there are no intervening elements or layers present. Like numbers referred to like elements throughout. As used herein, the term “and/or” includes any and all combinations of one or more of the associated listed items.

Spatially relative terms, such as “beneath”, “below”, “lower”, “above”, “upper” and the like may be used herein for ease of description to describe one element or feature's relationship to another element(s) or feature(s) as illustrated in the figures. It will be understood that the spatially relative terms are intended to encompass different orientations of the device in use or operation in addition to the orientation depicted in the figures. For example, if the device in the figures is turned over, elements describes as “below” or “beneath” other elements or features would hence be oriented “above” the other elements or features. Thus, term such as “below” may encompass both an orientation of above and below. The device may be otherwise oriented (rotated 90 degrees or at other orientations) and the spatially relative descriptors herein interpreted accordingly.

Although the terms first, second, etc. may be used herein to described various elements, components, regions, layers and/or sections, it should be understood that these elements, components, regions, layer and/or sections should not be limited by these terms. These terms are used only to distinguish one element, component, region, layer or section from another region, layer or section. Thus, a first element, component, region, layer or section discussed below could be termed a second element, component, region, layer or section without departing from the teachings of example embodiments.

The terminology used herein is for the purpose of describing particular embodiments only and is not intended to be limiting. As used herein, the singular forms “a”, “an” and “the” are intended to include the plural forms as well, unless the context clearly indicates otherwise. It will be further understood that the terms “includes” and/or “including”, when used in this specification, specify the presence of stated features, integers, steps, operations, elements, and/or components, but do not preclude the presence or addition of one or more other features, integers, steps, operations, elements, components, and/or groups thereof.

In describing example embodiments illustrated in the drawings, specific terminology is employed for the sake of clarity. However, the disclosure of this patent specification is not intended to be limited to the specific terminology so selected and it is to be understood that each specific element includes all technical equivalents that operate in a similar manner.

Referring now to the drawings, wherein like reference numerals designate identical or corresponding parts throughout the several views, example embodiments of the present patent application are described.

Referring to FIG. 1 of the drawings, a cross-sectional diagram illustrating an image forming apparatus 1 according to at least one example embodiment is described.

The image forming apparatus 1 includes an image carrier 2, a charge roller 3, an exposure unit 4, a development unit 5, a transfer roller 6, a cleaning unit 7, a fixing unit 8, and an output tray 9, a sheet feed unit 11, an attachable/detachable feed tray 12, and/or a pair of registration rollers 14. The sheet feed unit 11 includes a feed roller 13. The feed tray 12 contains a sheet stack 10.

In operation, the image carrier 2, which may be a photoconductive drum is driven to rotate clockwise in the drawing. The charge roller 3 charges a surface of the rotating image carrier 2 with a selected polarity. After charging, the exposure unit 4 scans the surface of the image carrier 2 with a modulated laser beam to form an electrostatic latent image thereon. Then, the development unit 5 converts the electrostatic latent image to a visible toner image.

In the sheet feed unit 11, the feed roller 13 rotates to remove an uppermost recording medium from the sheet stack 10. The removed recording medium is held by the pair of registration rollers 14, and at a given time is moved to a nip defined by the image carrier 2 and the transfer roller 6.

When the recording medium enters the nip, a given voltage is applied to the transfer roller 6 so that the toner image is transferred onto a surface of the recording medium facing the image carrier 2.

After image transfer, the cleaning unit 7 removes residual toner particles from the surface of the image carrier 2, and the recording medium enters the fixing unit 8. In the fixing unit 8, a fixing roller and a pressure roller apply heat and pressure to the recording medium passing therethrough so as to fix the toner image thereon. Thereafter, the recording medium is sent to the output tray 9.

During such printing process, a recording medium is conveyed along a transport path A indicated by arrows in FIG. 1. As shown in the drawing, the transport path A extends upward from the feed tray 12 to the output tray 9 within the image forming apparatus 1. The transport path A is defined by surfaces of components of the image forming apparatus 1, and is vertically bent to form a curved portion X immediately downstream from the feed roller 13 and a curved portion Y immediately downstream from the fixing unit 8. At each of the curved portions X and Y, a conveyed recording medium is turned to change direction of transport. Turning the recording medium may be facilitated by providing guide assemblies at portions along the transport path A, such as the curved portions X and Y, or any portions that may support a conveyed recording medium.

Referring now to FIG. 2A, an enlarged, partial cross-sectional view illustrating the image forming apparatus 1 having a guide assembly 20 is described.

In FIG. 2A, the guide assembly 20 is mounted adjacent to the feed roller 13. The guide assembly 20 has a concave guide surface to form a part of the transport path A corresponding to an outer bend of the curved portion X.

Upon reaching the curved portion X, a recording medium removed by the feed roller 13 moves upward along the guide assembly 20 with a leading edge against the concave guide surface. As a result, the leading edge enters a nip defined by a pair of guide rollers, for example, which causes the recording medium to turn to change direction of transport at the curved portion X.

Referring to FIG. 2B, an enlarged, partial cross-sectional view illustrating the image forming apparatus 1 having a guide assembly 20′ is described.

In FIG. 2B, the guide assembly 20′ is mounted on the feed tray 12 in addition to the guide assembly 20 of FIG. 2A. The guide assembly 20′ has a guide surface to form a part of the transport path A corresponding to an inclined surface of the feed tray 12.

Upon reaching the inclined surface of the feed tray 12, a recording medium removed by the feed roller 13 moves toward the curved portion X along the guide assembly 20′ with a leading edge against the guide surface. Upon reaching the curved portion X, the recording medium moves upward along the guide assembly 20 with the leading edge against the concave guide surface. As a result, the leading edge enters a nip defined by a pair of guide rollers, for example, which causes the recording medium to turn to change direction of transport at the curved portion X.

The image forming apparatus 1 with such a configuration may be used to perform printing on self-adhesive products, such as stickers, labels, and stamps, containing glue or adhesive material sandwiched between layers. In printing on a self-adhesive recording medium, the adhesive material may leak out or rub off from edges to contaminate the surface of the transport path A. As shown in FIGS. 2A and 2B, the guide assembly receives the leading edge of a recording medium at the guide surface, which is therefore prone to collect adhesive contaminants thereon. When accumulated over time, these adhesive contaminants may obstruct the transport path A, causing malfunctions such as paper creases and jams during media transport.

Referring now to FIG. 3, an example schematic illustration of a guide assembly 20 a for use in the image forming apparatus 1 is described.

As shown in FIG. 3, the guide assembly 20 a includes a surface plate 21 a and a base 22 a. The surface plate 21 a has a first surface 23 a, a second surface 24 a, and a pair of holes 26 a, not fully shown. The base 22 a has a pair of arms 25 a and a third surface 27.

In the guide assembly 20 a, the surface plate 21 a is symmetrical in cross section about a median plane. The first and second surfaces 23 a and 24 a are identical in size and shape and provided on opposite sides of the surface plate 21 a. In example embodiments, the third surface 27 may be identical in size and shape to each of the first and second surfaces 23 a and 24 a.

The pair of holes 26 a and the pair of arms 25 a form a snap-fit engagement. This snap-fit engagement allows the guide assembly 20 a to have a disassembled form, e.g., disassembled into the surface plate 21 a and the base 22 a, or to have one of first and second assembled forms. In the first assembled form, the surface plate 21 a may be removably connected to the base 22 a with the first surface 23 a facing out and the second surface 24 a facing the third surface 27. In the second assembled form, the surface plate 21 a may be removably connected to the base 22 a with the second surface 24 a facing out and the first surface 23 a facing the third surface 27.

In addition, the size and shape of the guide assembly 20 a are appropriately designed to fit a selected portion of the image forming apparatus 1, such as the curved portions X and Y, or any portions that may support a conveyed recording medium.

The guide assembly 20 a may be mounted at a portion of the transport path A in one of the first and second assembled forms and the disassembled form. When provided in the first assembled form, the guide assembly 20 a receives and guides a conveyed recording medium at the first surface 23 a. When provided in the second assembled form, the guide assembly 20 a receives and guides a conveyed recording medium at the second surface 24 a. When provided in the disassembled form, e.g., only the base 22 a is mounted, the guide assembly 20 a receives and guides a conveyed recording medium at the third surface 27.

For example, the guide assembly 20 a is initially mounted in the first assembled form. When the first surface 23 a collects adhesive contaminants through use, the guide assembly 20 a may be remounted in the second assembled form. In an environment where printing on self-adhesive products is rarely performed, such maintenance may be sufficient for preventing malfunctions during media transport due to accumulated adhesive contaminants.

Further, when the second surface 24 a collects adhesive contaminants through use, the guide assembly 20 a may be remounted in the disassembled form. Even in an environment where printing on self-adhesive products is frequently performed, such maintenance may be sufficient for preventing malfunctions during media transport due to accumulated adhesive contaminants.

Additionally, the disassembled form is also intended to work in case the guide assembly 20 a is mounted without the surface plate 21 a thereon due to an inadvertent omission in maintenance, for example.

In the embodiments, media transfer along a corresponding part is performed in a slightly different manner depending on whether the surface plate 21 a is used (e.g., in the first or second assembled form) or not used (e.g., in the disassembled form) due to a dimensional variation. In example embodiments, the surface plate 21 a may have a relatively thin profile to reduce this variation so that it does not cause significant inconsistencies in transport performance.

Referring now to FIG. 4, an example schematic illustration of another guide assembly 20 b for use in the image forming apparatus 1 is described.

As shown in FIG. 4, the guide assembly 20 b includes a surface plate 21 b and a base 22 b. The surface plate 21 b has a first guide surface 23 b, a second guide surface 24 b, and a pair of holes 26 b, not fully shown. The base 22 b has a pair of arms 25 b, not shown, a rotatable brush 28, and a motor 29.

In the guide assembly 20 b, the surface plate 21 b may be configured in a similar manner to the surface plate 21 a. The rotatable brush 28 has bristles of rigid material. The motor 29 serves to rotate the rotatable brush 28.

The pair of holes 26 b and the pair of arms 25 b form a snap-fit engagement. This snap-fit engagement allows the guide assembly 20 b to have one of first and second assembled forms. In the first assembled form, the surface plate 21 a may be removably connected to the base 22 b with the first surface 23 b facing out and the second surface 24 b in contact with the bristles of the rotatable brush 28. In the second assembled form, the surface plate 21 b may be removably connected to the base 22 b with the second surface 24 b facing out and the first surface 23 b in contact with the bristles of the rotatable brush 28.

In addition, the size and shape of the guide assembly 20 b are appropriately designed to fit a selected portion of the image forming apparatus 1, such as the curved portions X and Y, or any portions that may support a conveyed recording medium.

The guide assembly 20 b may be mounted and function at a portion of the transport path A in one of the first and second assembled forms in a similar manner to the guide assembly 20 a. The rotatable brush 28 performs cleaning of the first and second surfaces 23 b and 24 b.

For example, the guide assembly 20 b is initially mounted in the first assembled form. When the first surface 23 b collects adhesive contaminants through use, the guide assembly 20 b may be remounted in the second assembled form so that the rotatable brush 28 removes the contaminants from the first surface 23 b at a given time during operation. When the second surface 24 b collects adhesive contaminants through use, the guide assembly 20 b may be again remounted in the first assembled form so that the rotatable brush 28 removes the contaminants from the second surface 24 b at a given time during operation. Even in an environment where printing on self-adhesive products is constantly performed, such maintenance may be sufficient for preventing malfunctions during media transport due to accumulated adhesive contaminants.

Referring now to FIGS. 5A and 5B, example schematic illustrations of another guide assembly 20 c for use in the image forming apparatus 1 are described.

As shown in FIGS. 5A and 5B, the guide assembly 20 c includes a surface member 31 and a substrate 32. The surface member 31 includes a plurality of layers 33.

In the guide assembly 20 c, the plurality of layers 33 are formed of sheets superimposed and removably bonded together. The surface member 31 is removably bonded to a surface of the substrate 32.

In addition, the size and shape of the guide assembly 20 c are appropriately designed to fit a selected portion of the image forming apparatus 1, such as the curved portions X and Y, or any portions that may support a conveyed recording medium.

The guide assembly 20 c is mounted at a portion of the transport path A with the surface member 31 and the substrate 32 bonded together. The guide assembly 20 c receives and guides a conveyed recording medium at an outermost sheet of the plurality of layers 33. When the outermost sheet collects adhesive contaminants through use, the contaminated sheet is stripped off and discarded to be replaced with an unused underlying sheet. Thereby, the guide assembly 20 c may be remounted with an uncontaminated guide surface until the sheets of the plurality of layers 31 are finished up. Even in an environment where printing on self-adhesive products is constantly performed, such maintenance may be sufficient for preventing malfunctions during media transport due to accumulated adhesive contaminants.

Referring now to FIG. 6, an example schematic illustration of another guide assembly 20 d for use in the image forming apparatus 1 is described.

As, shown in FIG. 6, the guide assembly 20 d includes a surface member 41 and a substrate 42. The substrate 42 has a sight hole 44 and a cover 45.

In the guide assembly 20 d, the surface member 41 is made of a transparent material such as plastic, which may be a plate or a plurality of layers. The surface member 41 has an outer surface to be used as a guide surface and an opposite inner surface removably attached to an inner surface of the substrate 42 by bonding or by any engagement means. The sight hole 44 is formed through the substrate 42 with any desired shape and dimension. The sight hole 44 allows condition of the guide surface of the surface member 41 to be visually inspected from outside when the guide assembly 20 d is mounted. The cover 45 is removably attached to conceal the sight hole 44.

In addition, the size and shape of the guide assembly 20 d are appropriately designed to fit a selected portion of the image forming apparatus 1, such as the curved portions X and Y, or any portions that may support a conveyed recording medium.

The guide assembly 20 d is mounted at a portion of the transport path A so that the surface member 41 receives and guides a conveyed recording medium at the guide surface. When it is determined that the guide surface needs maintenance by visual inspection through the sight hole 44, the guide assembly 20 d is detached so as to clean or replace the guide surface. Such maintenance of the guide surface is performed in an appropriate manner depending on the configuration of the surface member 41.

Example embodiments enable effective maintenance of the guide assembly for preventing malfunctions during media transport due to accumulated adhesive contaminants. Further, example embodiments enable to proper determination of when to perform the preventive maintenance through visual inspection. Such a determination based on the visual inspection is more reliable and reasonable than estimating the guide surface condition from a total number of recording media conveyed through the transport path A, which is not necessarily proportional to the number of adhesive recording media conveyed to contaminate the guide surface.

Numerous additional modifications and variations are possible in light of the above teachings. It is therefore to be understood that within the scope of the appended claims, the disclosure of this patent specification may be practiced otherwise than as specifically described herein.

Further, elements and/or features of different example embodiments may be combined with each other and/or substituted for each other within the scope of this disclosure and appended claims.

Example embodiments being thus described, it will be obvious that the same may be varied in many ways. Such variations are not to be regarded as a departure from the spirit and scope of the present specification, and all such modifications as would be obvious to one skilled in the art are intended to be included within the scope of the following claims. 

1. An image forming apparatus, comprising: a transport path configured to convey a recording medium; and a guide assembly configured to guide the recording medium in the transport path, the guide assembly including; a surface member having first and second surfaces of a similar shape on opposite sides thereof; and a base member configured to support the surface member; wherein the surface member and the base member are removably connected in one of first and second assembled forms, the first surface serving to receive the recording medium and the second surface facing the base member in the first assembled form, and the second surface serving to receive the recording medium and the first surface facing the base member in the second assembled form.
 2. The image forming apparatus according to claim 1, wherein the base member has a cleaning device serving to clean the second surface in the first assembled form and to clean the first surface in the second assembled form.
 3. The image forming apparatus according to claim 1, wherein the connecting element forms a snap-fit engagement.
 4. The image forming apparatus according to claim 1, wherein the base member has a guide surface facing the surface member in one of the first and second assembled forms, the guide surface serving to receive the recording medium when the surface member is removed from the base member.
 5. The image forming apparatus according to claim 1, wherein the guide assembly is located at an outer bend of a curved portion of the transport path and serves to turn the recording medium therealong.
 6. The image forming apparatus according to claim 1, further comprising an attachable/detachable feed tray configured to contain the recording medium, wherein the guide assembly is located at a portion of the feed tray and serves to remove the recording medium therealong.
 7. An image forming apparatus, comprising: a transport path configured to convey a recording medium; and a guide assembly configured to guide the recording medium in the transport path, the guide assembly including; a surface member having a plurality of layers superimposed and removably bonded together, configured to receive the recording medium at an outermost layer of the plurality of layers; and a base member configured to support the surface member.
 8. The image forming apparatus according to claim 7, wherein the plurality of layers include a plurality of sheets.
 9. The image forming apparatus according to claim 7, wherein the guide assembly is located at an outer bend of a curved portion of the transport path and serves to turn the recording medium therealong.
 10. The image forming apparatus according to claim 7, further comprising an attachable/detachable feed tray configured to contain the recording medium, wherein the guide assembly is located at a portion of the feed tray and serves to remove the recording medium therealong.
 11. The image forming apparatus according to claim 7, wherein the outermost layer is removed for maintenance.
 12. An image forming apparatus, comprising: a transport path configured to convey a recording medium; and a guide assembly configured to guide the recording medium in the transport path, the guide assembly including; a transparent surface member configured to receive the recording medium at a guide surface thereof; and a base member having a sight hole, configured to support the surface member so that condition of the guide surface is observable through the sight hole.
 13. The image forming apparatus according to claim 12, wherein the base member has an attachable/detachable cover to conceal the sight hole.
 14. The image forming apparatus according to claim 12, wherein the connecting element forms a snap-fit engagement.
 15. The image forming apparatus according to claim 12, wherein the guide assembly is located at an outer bend of a curved portion of the transport path and serves to turn the recording medium therealong. 